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BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Revenue Recognition (Details) $ in Thousands | 12 Months Ended
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Sep. 30, 2025 USD ($)
Disaggregation of Revenue [Line Items] |
Reduction of revenue for economic value of tax credits to be transferred | $ 52,989
Benefit to tax provision related to tax credits | (58,369)
Liability for credits to be transferred | $ 12,985
Minimum |
Disaggregation of Revenue [Line Items] |
Performance obligation and payment period | 30 days
Maximum |
Disaggregation of Revenue [Line Items] |
Performance obligation and payment period | 60 days

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